Melanoma therapy via peptide-targeted {alpha}-radiation

Area of Science:

• Nuclear Medicine
• Oncology
• Radiopharmaceutical Science

Background:

• Alpha radiation offers high linear energy transfer, effective against radioresistant tumors like melanoma.
• Melanoma is a significant health concern, necessitating novel therapeutic strategies.

Purpose of the Study:

• To evaluate the therapeutic efficacy of a unique melanoma-targeting peptide conjugated with an alpha-particle-emitting radionuclide.
• To assess the potential of (212)Pb[DOTA]-Re(Arg(11))CCMSH as a targeted radionuclide therapy for melanoma.

Main Methods:

• The study utilized the B16/F1 mouse melanoma model.
• The melanoma-targeting peptide 1,4,7,10-tetraazacyclodecane-1,4,7,10-tetraacetic acid (DOTA)-Re(Arg(11))CCMSH was radiolabeled with lead-212 ((212)Pb).
• Biodistribution and therapy studies were conducted.

Main Results:

• (212)Pb[DOTA]-Re(Arg(11))CCMSH demonstrated rapid tumor uptake and retention.
• Tumor radiation dose was estimated at 61 cGy/μCi (212)Pb.
• Treatment extended mean survival in melanoma-bearing mice, with 45% achieving disease-free survival at the highest dose.

Conclusions:

• The radiopharmaceutical significantly reduced melanoma tumor growth rates and extended survival.
• Complete remission was observed in a notable percentage of treated mice.
• (212)Pb[DOTA]-Re(Arg(11))CCMSH shows promise as a radiopharmaceutical for melanoma targeted radionuclide therapy.